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Topic: Metallic Hydrogen is real! (Read 21440 times)

How much of a case has been made that metallic hydrogen will be metastable and up to what pressure? I couldn't find any information on that but thought I had gathered from somewhere that metastability does not imply anything like ambient pressure or that it can be used to build structures, as I saw thrown around in a few article headings.

What is claimed here is just that we have created some metallic hydrogen, right? What sort of confidence is there in it's properties?

The quoted Isp of 1700s from the above conference paper is based on assuming that metastable metallic hydrogen exists at relatively low pressure, and using it as a monopropellant, from the heat of recombination to molecular hydrogen.

How much of a case has been made that metallic hydrogen will be metastable and up to what pressure? I couldn't find any information on that but thought I had gathered from somewhere that metastability does not imply anything like ambient pressure or that it can be used to build structures, as I saw thrown around in a few article headings.

What is claimed here is just that we have created some metallic hydrogen, right? What sort of confidence is there in it's properties?

Seems that since synthesizing last month the folks at Harvard have been keeping the sample in liquid nitrogen so far. After poking it some more, Dr. Silvera has said that there looking at several potential methods of gradually heating it up. Since they're actively keeping it cold right now, I figure we'll have to know if it's metastable at normal temps within a relatively short period of time.

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I love Star Trek more than anyone, but we don't (and shouldn't) spend tens of billions of dollars on space programs for fun

also its not as simple as solid, liquid and condensed gas... the articles seem to say that the solid form has at least three probably different organizational forms.

That's the most critical part for consideration of a solid plasma.

In Frank Chen's unpublished continuation to his Plasma Physics book, (which I have a draft copy of), he discusses theoretical solid plasmas - the organization of the "material" will matter.

(Around this time had a discussion/notes of a fusion "combustion chamber" based on a solid plasma, however was told that no one would ever build a large enough vehicle for its use, since the Saturn V was considered "uneconomic" due to size. )

yeah. uneconomic. as in the govt didn't want to pay for it once we won the space race. but there is lots of neat stuff coming up that i, as a laymen type science dilitante, barely understand. like the nucleus of heavy atoms can assume a hollow form. I read that just recently. all the protons and neutrons form a structure something like a blastula. which is really weird.

The idea has been been around since at least 1970 when RL Forward of Hughes labs did a project for IIRC the USAF on (IIRC) "Energetic materials" along with things like antimatter and N8 (yes that's a ring of 8 Nitrogen atoms). However I think they were still expecting metallic H2 to show up around the 25GPa, rather than the actual level 18x higher.

Various groups seem to be getting close to making N8 but these groups specialize in making and handling stuff like this. I saw a chemistry blog it was mentioned on. The thing they'd made violently decomposed when exposed to the IR beam in a spectrometer

This suggest they will be lowering the pressure on this sample very carefully.

Strictly it's not. Orion (and the fission fragment rocket) are both systems with high (relative to chemical) fuels. NERVA was targeting 900-950secs at most and if liquid metallic hydrogen can be made to exist at reasonable pressures (IE 2-3 atm) then it's T/W will also be 10-20x better than NERVA as well.

No. The Isp for a NTR is set by the molecular weight of the fuel, the temperature and pressure you raise it to and the size of the nozzle you expand the flow through.

A big nozzle can put a 10s of secs on an Isp, not 800secs.

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BFS. The worlds first Methane fueled FFORSC engined CFRP structured A380 sized aerospaceplane tail sitter capable of flying in Earth and Mars atmospheres. BFR. The worlds biggest Methane fueled FFORSC engined CFRP structured booster for BFS. First flight to Mars by end of 2022. Forward looking statements. T&C apply. Believe no one. Run your own numbers. So, you are going to Mars to start a better life? Picture it in your mind. Now say what it is out loud.

My question is: how much does it cost to make enough metallic hydrogen for a SSTO launch with 25 tonnes of payload? If it costs too much, then there is little point to it unless there is a path towards bringing costs down.

Until last month the price per kg was infinity, now after producing however much they did it's probably down into the mere quadrillions- so one month from now it should be completely free.

If it is a room temperature super conductor, they'll certainly be interested in producing as much of it as they can... who knows how easy or difficult it will be to produce it in 30, or 50, or 100 years, fingers crossed...

Hadn't heard about metallic hydrogen as a potential chemical fuel before, but apparently it's been theorized for some time. Are there any other interesting theoretical fuels out there which might be synthesized and haven't been yet?

yeah. go to project rho and look at their engine table. several of the fuels listed there are pretty much what you are asking about. E.G; metastable helium.

if you could make atoms out of unusual particles like magnetic monopoles the energy released by breaking their *chemical* bonds could release more energy that antimatter or certainly atomic reactions. this is because the energy is inversely proportional to the length of the bonds whether electronic bonds or nuclear bonds. the bonds of magnetic monopole matter would be 2000 time shorter than those in regular matter and antimatter. and breaking a magnetic monopole atoms nucleus apart or fusing them would make more energy still than breaking electronic bonds. so if you could find either monopoles or some other suitable nucleon and electron substitute you could vastly out-perform even antimatter engines.

we don't have monopoles but we have created synthetic atoms out of stuff that doesn't normally form atoms such as kaons and muons. they are very unstable and last a tiny amount of time before breaking up. but there is reason to hope that some combination or some amount of a material like this may be more persistent.

Neutrons die in 11 or so minutes when alone but are stable possibly forever in an atomic nucleus. Likewise kaonium (or was it muonium?) lasts longer than individual particles of their species.

No, you cannot exceed e=mc^2. Any energy that you store in "chemical bonds" will simply show up as extra mass of the fuel. The energy per unit mass cannot surpass matter/antimatter.

I didn't say you could. E=MC^2 is germane though. only-- in the case of massive monopoles packed into a lot less space than say the nucleons involved in antimatter annihilation reactions there is a heck of a lot more M and consequently a heck of a lot more E. Also the nuclear and electronic bonding energy scales inversely with the bonding length and the bonding length of an atom made of monopoles would be orders of magnitude shorter and thus more energetic.

Now assuming we can't haz monopoles but can find something on the scale of axions or even up to a similar mass to kaons or muons the energy available for other synthetic atoms might be a lot less because the scaling would be different and probably larger than hypothetical monopoles but still probably less than ordinary matter atoms. thus even if you are constrained by E=MC^2 all the terms except C in that equation are variables.

depending on the type of monopole posited atoms made with them could be as small as:

{Taken from a hard fiction and hard fiction based game site. But large parts of the science they use in their project are based on peer reviewed science papers. this physics stuff on their site used to be footnoted with links to first sources, cites and references but that is no longer the case since they reorganized the site.}

Quote

The smallest magatoms have diameters of 3E-19 m, 300 million times smaller than an atom of conventional matter. As a typical magatom is 10,000 times heavier than a typical conventional atom, magmatter�s typical density is 1E33 kg/m3. Since force is energy per unit distance, the force needed to break a magchemical bond is larger than that needed to break an electronic chemical bond by a factor of the energy scaling (300 GeV / 13.7 eV) divided by the length scaling, or 7 million trillion (7E18). The strength of a material is usually defined as the force per unit area required to make the material fail. Since each magchemical bond can withstand 7E18 times greater force, and there are (300 million)2 times more bonds per unit area, the strength of magmatter is about 8E35 times greater than that of its normal matter equivalent.

And that would be the energy in a monopole atom's chemical bond; not a monopole atom's nuclear bond. Of course monopoles may not exist or may not be accessible even if they do exist, but the same principle would apply to other synthetic atoms made of particles other than protons and neutrons and electrons or their antimatter equivalents.

Synthetic atoms of Kaons, Muons and hybrids of AM and matter particles have been made by researchers. Muonium (?) has a half life longer than naked muons though they only persist longer by a tiny bit. Neutrons have a half life of 11 minutes naked or for all intents and purposes forever in a stable atom except in radioactive nuclei. It is therefore not unreasonable to consider it possible for some synthetic atomic arrangement to be permanently stable as well.

We are still discovering fundamental facts about particle physics, nuclear chemistry and condensed matter physics. Last week i read that sometimes the nucleons in the nucleus of heavy atoms assumes a hollow spherical configuration despite what is known in the state of the art about nucleonic shells and the structure of an atom.

EDIT: The short version of the above is that because there would presumably be much more mass and energy packed into a smaller space synthetic matter could provide more energy than antimatter even though all are constrained by the mass energy equivalence in the famous equation.

EDIT: The short version of the above is that because there would presumably be much more mass and energy packed into a smaller space synthetic matter could provide more energy than antimatter even though all are constrained by the mass energy equivalence in the famous equation.

And, what's the point in a spaceship about it's size?It has no effect on ISP.

I think that the only problem it solves is the unstable form of antimatter. Antimatter seems to unstable to allow 1 matter atom x 1 antimatter atom ratio in safety conditions in the same spaceship.Other forms of matter could be more stable and have better practical ratios allowing very near ISP to a theorical perfect antimatter spacechip.ISP levels enough powerfull to allow interstellar travel viable. "Slow" (from human perspective) but practical for near stars.

No, you cannot exceed e=mc^2. Any energy that you store in "chemical bonds" will simply show up as extra mass of the fuel. The energy per unit mass cannot surpass matter/antimatter.

And they are not actually suggesting you can. they are suggesting that by making atoms which are smaller (because they are made of unconventional particles to begin with) they would have stronger, shorter bonds. This creates (theoretically) matter with "impossible" densities.

Of course you're now making fuel atom by atom, which is likely to be pretty slow.

BFS. The worlds first Methane fueled FFORSC engined CFRP structured A380 sized aerospaceplane tail sitter capable of flying in Earth and Mars atmospheres. BFR. The worlds biggest Methane fueled FFORSC engined CFRP structured booster for BFS. First flight to Mars by end of 2022. Forward looking statements. T&C apply. Believe no one. Run your own numbers. So, you are going to Mars to start a better life? Picture it in your mind. Now say what it is out loud.

Speculating about the metastability of metallic hydrogen can maybe be called discussion about Advanced Concepts, but magnetic monopoles, (meta)stable kaonium etc. takes this IMO to New Physics with the rest of the 'out there' stuff.

EDIT: The short version of the above is that because there would presumably be much more mass and energy packed into a smaller space synthetic matter could provide more energy than antimatter even though all are constrained by the mass energy equivalence in the famous equation.

I don't think space taken by fuel is an important limit when dealing with things like antimatter.

If monopoles exist a better use for them may be to catalyze the decay of protons. You get matter energy conversion without the expensive and dangerous antimatter.

It could substantially improve the Isp of an Orion pulsed nuclear rocket - if used as the implosive driver of fission bombs, and perhaps also adding a metastable pit of Deuterium or Tritium metal (with 30 or 45x liquid protium density) to the core of a fission bomb could greatly enhance their yields.

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The glass is neither half full nor half empty, it's just twice as big as it needs to be.

I think a big part of what's going on with metallic hydrogen is that the hydrogen is essentially in atomic rather than molecular form. To burn a mole of molecular hydrogen, first you need to break a mole's worth of H-H bonds: that takes 436 kJ. With metallic hydrogen, the atoms need be broken out of the metallic matrix, but that probably takes a lot less energy. So, the heat released by burning metallic hydrogen is probably something like the heat of combustion of molecular hydrogen, 286 kJ/mol, plus 436 kJ/mol = 722 kJ/mol.

Now, could we get some metallic oxygen, too? Breaking an O=O bond takes 498 kJ/mol, and we need half a mole per mole of hydrogen, so that's a total energy release of about 971 kJ/mol. Or, going into totally wild speculation, is a hydrogen-oxygen alloy possible?

Now, could we get some metallic oxygen, too? Breaking an O=O bond takes 498 kJ/mol, and we need half a mole per mole of hydrogen, so that's a total energy release of about 971 kJ/mol. Or, going into totally wild speculation, is a hydrogen-oxygen alloy possible?

By definition, no. Alloys exist as combinations of metals because of the properties of metals - which Oxygen most definitely is not . Hydrogen is an unusual case; it's on the far left side of the periodic table because it's expected to be a metal, were it not for the quantum mechanics involved in the element's simplicity.

Now, could we get some metallic oxygen, too? Breaking an O=O bond takes 498 kJ/mol, and we need half a mole per mole of hydrogen, so that's a total energy release of about 971 kJ/mol. Or, going into totally wild speculation, is a hydrogen-oxygen alloy possible?

By definition, no. Alloys exist as combinations of metals because of the properties of metals - which Oxygen most definitely is not . Hydrogen is an unusual case; it's on the far left side of the periodic table because it's expected to be a metal, were it not for the quantum mechanics involved in the element's simplicity.

Oxygen will convert to a metallic allotrope at about 132 GPa. Many non-metal atoms have a metallic allotrope at sufficient pressures.

It just means that when pressures are sufficient to pack the atoms so tightly together that the valence electrons begin to migrate freely through the substance then it will demonstrate metallic properties.

As far as I know, most of these metallic allotropes are not meta-stable and probably not all that useful for spaceflight unless you have a way to sustain those pressures without using massive containing structures.

Metallic deuterium would allow self-detonating fusion devices. Friedwardt Winterberg has a design for a non-fission triggered D-T device (it's in one of his papers on viXra, since the arXiv wouldn't allow it.) He used standard chemical explosives in a rather complicated process. Such explosives pack the equivalent of ~350 s Isp. An implosion device made of solid metallic deuterium wouldn't need high explosives, since it would pack ~x10 the energy or so. And it'd be fusion fuel. Just squirt some tritium into the very centre.

Also, superconducting rings of metallic hydrogen could be launched via a linear accelerator to be mass-beam pellets to push spacecraft. Ramming into a magnetic field around the vehicle at high speed would probably cause the superconductivity to quench, blasting the ring into high speed hydrogen plasma.

Now, could we get some metallic oxygen, too? Breaking an O=O bond takes 498 kJ/mol, and we need half a mole per mole of hydrogen, so that's a total energy release of about 971 kJ/mol. Or, going into totally wild speculation, is a hydrogen-oxygen alloy possible?

By definition, no. Alloys exist as combinations of metals because of the properties of metals - which Oxygen most definitely is not . Hydrogen is an unusual case; it's on the far left side of the periodic table because it's expected to be a metal, were it not for the quantum mechanics involved in the element's simplicity.

Oxygen will convert to a metallic allotrope at about 132 GPa. Many non-metal atoms have a metallic allotrope at sufficient pressures.

It just means that when pressures are sufficient to pack the atoms so tightly together that the valence electrons begin to migrate freely through the substance then it will demonstrate metallic properties.

As far as I know, most of these metallic allotropes are not meta-stable and probably not all that useful for spaceflight unless you have a way to sustain those pressures without using massive containing structures.